I put some more work into my Pyxis of Pandemonium deck. I couldn't get it to work for me without premiums, so I broke down and bought them. The mana is a lot smoother now, which is important, because it needs to get to 7 mana most of the time before it really starts working. It's still not quite there yet, so I would appreciate any thoughts/feedback.
Pandemonium (premium)
Spells (36)
2 x
Traveler's Amulet2 x
Pyxis of Pandemonium4 x
Lone Missionary3 x
Wall of Omens2 x
Banisher Priest4 x
Phyrexian Rager3 x
Darksteel Ingot2 x
Seance2 x
Jalira, Master Polymorphist2 x
Gravedigger1 x
Baneslayer Angel2 x
Mercurial Pretender1 x
Shadowborn Demon1 x
Angelic Edict1 x
Soul of Ravnica1 x
Resolute Archangel2 x
Rune-Scarred Demon1 x
Kozilek, Butcher of TruthLands (24)
5 x
Plains3 x
Island4 x
Swamp4 x
Azorius Guildgate4 x
Dimir Guildgate4 x
Orzhov GuildgateThis deck generally aims to take advantage of EtB effects. Those EtB effects can be triggered Jalira and Pyxis to keep the opponent guessing, and they can all be recurred by Seance. Some thoughts I have about specific cards:
-Rune-Scarred demon has pretty much been the star of the deck. Once he comes out (through hard-casting, Seance, Jalira, or Pyxis), unless I'm going to die before I untap again, I'm usually in pretty good shape.
-Mercurial Pretender is second-place in this deck. Once your first Rune-Scarred demon hits the board, you can pull out up to three more (one at a time) by taking mercurial and turning him into rune-scarred. If your mana and your opponent allow, you can keep bouncing him back to your hand and recasting him for repeated tutoring in the presence of a rune-scarred demon (or any other EtB effect you need at the moment).
-Seance works very well here. Besides obviously triggering all of your EtBs a second time, you can generate high CMC EtB effects early game (e.g. with a rune-scarred demon or resolute archangel, for example, in the GY and seance on the board).
-One copy of Angelic Edict can help you deal w/ enchants that may otherwise be very troublesome, e.g. sanguine bond or beastmaster ascension. With Kozilek, it can be reused, and with rune-scarred, it can be fetched.
-Jalira, in theory, works well. In practice, she usually gets removed before she can start cycling my EtB effects, or I'm under significant pressure and have no creatures to sacrifice to her. Should I replace her?
-If seance wasn't enough, Gravediggers give us even more EtB recursion. I initially used 4 of these, but found that I often had more capacity to recur creatures than I had creatures to recur, so cut it down to 2.
-Kozilek can ruin Seance, but overall he's more helpful than harmful, imo. Seance is useful here, but not necessary to win. Kozilek wins games, and he protects against mill. The only time I dislike seeing him is in my opening hand.
-Soul of Ravnica is decent. A 6/6 flying is always welcome (if this deck wins, it often does so with fliers). But he has no EtB, and his draw effect, while useful in a 3-color deck, is hard to pay for when you're under a lot of pressure.
-Pyxis of Pandemonium - I could honestly cut this, but it's kind of the theme of the deck, so I've resisted doing so. I wanted a deck that could take advantage of Pyxis but wouldn't be completely useless without it. It's best in the opening hand, but even then you need to survive to 7 mana to use it. And while this deck has 26 creatures to put into play with it, some other decks (e.g. lots of fatties or really high creature counts) might profit from Pyxis more than oneself. And of course, there's always the random chance that Pyxis rewards the opponent more than you even when your deck is better designed for it.